226 citations · 856 across the 20 of their papers we have counts for
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Electron spin resonance in S=1/2 antiferromagnets at high temperature
S. El Shawish, O. Cepas, S. Miyashita
We study the electron spin resonance (ESR) of low-dimensional spin systems at high temperature, and test the Kubo-Tomita theory of exchange narrowing. In finite-size systems (molec…
The incarnation of the Nersesyan-Tsvelik model in (NO)[Cu(NO3)3]
O. Volkova, I. Morozov, V. Shutov +8
The topology of the magnetic interactions of the copper spins in the nitrosonium nitratocuprate (NO)[Cu(NO3)3] suggests that it could be a realization of the Nersesyan-Tsvelik mode…
A Schwinger-boson approach to the kagome with Dzyaloshinskii-Moriya interactions: phase diagram and dynamical structure factors
L. Messio, O. Cepas, C. Lhuillier
We have obtained the zero-temperature phase diagram of the kagome antiferromagnet with Dzyaloshinskii-Moriya interactions in Schwinger-boson mean-field theory. We find quantum phas…
Quantum phase transition induced by Dzyaloshinskii-Moriya in the kagome antiferromagnet
O. Cepas, C. M. Fong, P. W. Leung +1
We argue that the S=1/2 kagome antiferromagnet undergoes a quantum phase transition when the Dzyaloshinskii-Moriya coupling is increased. For the system is in a moment-free…
How to detect weak emergent broken-symmetries of the Kagome antiferromagnet from Raman spectroscopy
O. Cepas, J. O. Haerter, C. Lhuillier
We show that the magnetic Raman response of a spin-liquid is independent of the polarizations of the light for triangular symmetries. In contrast, a ground-state that has a broken…
Theory of phonon-assisted "forbidden" optical transitions in spin-gapped systems
Olivier Cepas, Timothy Ziman
We consider the absorption of light with emission of one S(tot)=1 magnetic excitation in systems with a spin gap induced by quantum fluctuations. We argue that an electric dipole t…